Fighting Style (NOT!)
Perhaps the most immediately noticeable thing about the Ranger is the absence of a feature that's been traditional for most incarnations of Rangers - a choice between wielding two melee weapons or focusing on archery (which usually involves making multiple ranged attacks). Rangers have always been the multi-attackers.
The problem with that (a problem that the design team is well aware of) is that it's not enough of a schtick to justify a class. It's just weapon choice. It's a choice that any melee class should have the option of making (as 4E proved with its "Ranger clone" builds: the Tempest Fighter and Whirling Barbarian). Plus there's the fact that it does absolutely nothing to replicate one of the most iconic rangers of all in fiction, Aragorn.
I don't play a Ranger because I want to be "a Fighter, but with two weapons." It's one of my favorite classes, and you could more accurately say that I deal with the fact that the choice is usually baked into the class. No, I play a Ranger to be the guerilla-tactics, outdoorsy hunter guy. To me subtle nature spells and animal companions are both more in line with how I view Rangers than weapon choice (though there are strong archery traditions to the archetype; it's the two-weapon fighting that I mostly don't get). So bonus points for slaying that sacred cow.
Ah, Ranger spellcasting. In 3.x it was so weak compared to a full caster that it might as well be ignored (though not to the egregious extent as the Ranger's half-strength animal companion that usually was ignored). In 4E it simply didn't exist. And yet, it's still something that makes sense to me.
If you're going to have it, then YES you should get it at 1st level. I'm a HUGE proponent of classes getting all of their main stuff right away. People play different classes for different reasons, but it usually boils down to "I want to be able to do ______." In 3.x I would always want to play a shapeshifter, and was always let down because we almost always played low level, and the Druid didn't get that yet. There's always room to get better at what you do as you level, but the main components of your class's identity should be useable out of the box.
As I hinted at before, the key to capturing the Ranger's feel is that their spells need to be SUBTLE. They shouldn't give up much (if any) raw combat power just because they get spells, because they're not going around slinging spells during combat. This spell list hits that mark perfectly. With Animal Friendship and Cure Wounds you could replicate Aragorn's abilities fairly well, even if his "spellcasting" wasn't as overt as D&Ds. And really, it's not something you have to (or should) play up as a Ranger. Cast your spells with little to no fuss and act like nothing unusual happened. Yours is a more humble spellcasting; you lack the flashiness (and raw power) of the Druid's. If the flashiest spell you've got is Fog Cloud and Spike Growth, you're a well-designed caster-Ranger.
I also like that, aside from Barkskin, you're also not using your spells to buff yourself up for combat. The 3.x Ranger was guilty of that. No, the Ranger should have the same baseline competency as the other martial classes. His spells are for utility. Occasionally healing, but mostly "exploration" based.
I'll just come out and say it that this incarnation of Favored Enemy is probably my favorite thing in the whole packet. This is coming from someone who normally HATES Favored Enemy mechanics. For largely the reasons that were explained in the podcast that was aired when this packet was released. The bonus is situational (what if the DM doesn't include those enemies?) and the result is that you're just a gimped Fighter most of the time, but when your moment comes to shine then the fight is usually anticlimactic because you can chew through it. Which leads to the DM to not want to include those enemies, and it's just a vicious loop.
So why is this version better? Well, it's applicable to a broad range of foes that have similar qualities to the one you specialize in, and the benefits are a lot more interesting than straight numerical bonuses. They're tangible concepts that make you feel like you have an actual ability.
Your first option is Brute Hunter, which means that you specialize in those monstrous humanoids that tend to fight in large groups. You're the guerrilla warrior that can take a larger force by surprise and win. This is very much my kind of Ranger. All of options give you advantage on checks to recall lore on your type of enemy, which is expected and works well. Then you get another 1st level feature, which for this option lets you keep your allies from being surprised (you're used to being on the lookout, and sneaking by even when there are many eyes watching out for YOU). Then there's a 2nd level feature, and an 8th level feature. At 2nd opportunity attacks made against you have disadvantage, allowing you to either retreat from a fight more easily or to move through a group to kill a priority target. At 8th you get a double cleave that can be used with ranged attacks. Yeah, you're very dangerous when outnumbered.
Next is the iconic Dragon Slayer. Starting from 1st level you're immune to fear. By 2nd you buff a subsequent attack when you hit a foe, dealing extra damage next round. Chip away at those "bag of hit points" monsters (as dragons tend to be). The capstone is Evasion, to protect you from things like Breath Weapons (half damage if you fail a Dex save, no damage if you pass even if you'd normally take half). Fights against dragons will still be appropriately tough, you're just good at taking the heat. You're more likely to not get burned to a crisp or run away.
Finally, we have Giant Killer. At 1st level you can use your reaction to halve damage taken from Large+ creatures (nice!). Your 2nd level ability is the same as Dragon Slayer's (I approve of avoiding redundancy when designing for similar concepts). As a capstone you can avoid the reach that giants will inevitably have (but plenty of other creatures as well). While outside of 5 ft melee attacks against you are made with disadvantage. If threatening reach is a thing in Next, these guys will be great at punching through that first line of defense.
Though the wording is a little weird, I like that melee damage scales as you level by multiplying your base damage die. It works better than gaining extra attacks (you reduce the total number of die rolls) or piling on static mods (as was the case in 4E, where your weapon's damage didn't matter all that much; made you wonder why you needed to roll a die to begin with). It's also a great way of keeping the melee classes at parity. It's no coincidence that the Druid's Dire Shape gives Wild Shape the same scaling ("why yes, we do acknowledge that you want to fight in melee, and here's how you keep up with Fighters").
Mostly it's a good sign that "this guy's better/worse at combat" isn't being used as a balancing point. You're not a gimped Fighter just because you get Favored Enemies and Spellcasting, you're a warrior who gives up the Fighter's maneuvers in order to get those things. You're both comparable as far as raw numbers are concerned, though, and that's what I want to see in a Ranger.